Access Denied to SQL Replication Snapshot folder

 I have a SQL server 2008 installed, Transactional(PULL) Replication has been implemented der,everthng was working fine but suddenly snapshots are failing to generate.When I execute the snapshot agent it shows me error that,

Access to the path 'path of a snapshot folder' is denied.

snapshot folder is shared to everyone with all securities,I can access the path through run.Folder is shared to SQL agent and main SQL service.

ANY HELP........?